By David Madden

PHILADELPHIA (CBS) - The CEO at Sunoco is stepping down at the end of the month after four years at the helm, overseeing changes that include a decision to get out of the oil refining business in favor becoming a retail operation. It’s a move that does not surprise many of those whose lives are changing along with the company.

Lynn Elsenhaus (right) will be replaced by current Chief Financial Officer Brian MacDonald. It’s a move that changes nothing for the 400 unionized workers at Sunoco’s Marcus Hook refinery who, come March 1st, will be on the unemployment line.

“She was brought in to methodically tear this place apart,” union head Dave Miller says. “She did what she was brought here to do and now she’s gonna move on.”

Meanwhile, hopes for a sale of the refinery are fading fast. Sunoco, in its change of management announcement, noted that no company has stepped forward to buy the Marcus Hook plant outright. So they’re looking into other alternatives.

As for the Philadelphia refinery, there’s been some interest, but without a sales agreement, operations will be idled there come July.